expect命令

expect介绍

​ 借助Expect处理交互的命令,可以将交互 过程如:ssh登录,ftp登录等写在一个脚本上,使之自动化完成.尤其适用于需 要对多台服务器执行相同操作的环境中,可以大大提高系统管理人员的工作效率

expect安装

[root@ansible ssh]# rpm -qa | grep expect
expect-5.45-14.el7_1.x86_64
[root@ansible ssh]# yum install expect

expect 语法

 expect [选项] [ -c cmds ] [ [ -[f|b] ] cmdfile ] [ args ] 

选项 
   -c：从命令行执行expect脚本，默认expect是交互地执行的   
          示例：expect -c 'expect "\n" {send "pressed enter\n"} 
   -d：可以输出输出调试信息   
          示例：expect  -d ssh.exp
    expect中相关命令 
          spawn：启动新的进程 
          send：用于向进程发送字符串 
          expect：从进程接收字符串 
         interact：允许用户交互
         exp_continue  匹配多个字符串在执行动作后加此命令 
 expect最常用的语法(tcl语言:模式-动作) 
  单一分支模式语法： 
        expect “hi” {send “You said hi\n"}     匹配到hi后,会输出“you said hi”，并换行
  多分支模式语法: 
        expect "hi" { send "You said hi\n" } \ "hehe" { send “Hehe yourself\n" } \ "bye" { send “Good bye\n" } 
  匹配hi,hello,bye任意字符串时,执行相应输出.等同如下:
       expect { "hi" { send "You said hi\n"} "hehe" { send "Hehe yourself\n"} "bye" { send “Good bye\n"} } 

自动拷贝文件到远程主机

​ 执行expect 不能以bash file 的方式来执行 (开启一个子shell进程)

必须通过  chmod +x file     ./file  这样的方式    (不会开启子shell进程,只在当前shell环境中执行)
expect 如果只交互一次如拷贝文件   结尾就使用   expect eof 
 如果需要连续交互如登录远程主机执行各种命令结尾就需使用   interact

读取配置文件自动执行ssh

1.安装expect 系统默认没有此命令

   yum install expect

2.创建配置文件

[root@ansible ssh]# vi hosts
192.168.31.134 root root
192.168.31.135 root root
192.168.31.136 root root

3.编写脚本

[root@ansible ssh]# ls
copykey.sh  hosts
[root@ansible ssh]# vi copykey.sh 
#!/bin/bash
if [ ! -f ~/.ssh/id_rsa ];then
 ssh-keygen -t rsa -P "" -f ~/.ssh/id_rsa
else
 echo "id_rsa has created ..."
fi
#分发到各个节点
while read line
  do
    user=`echo $line | cut -d " " -f 2`
    ip=`echo $line | cut -d " " -f 1`
    passwd=`echo $line | cut -d " " -f 3`
    expect <<EOF
      set timeout 10
      spawn ssh-copy-id $user@$ip
      expect {
        "yes/no" { send "yes\n";exp_continue }
        "password" { send "$passwd\n" }
      }
     expect "password" { send "$passwd\n" }
EOF
  done <  hosts

4.给脚本执行权限

  chmod +x copykey.sh

5.执行脚本

./copykey.sh

执行多条命令

 #!/usr/bin/expect 
set ip [lindex $argv 0] 
set user [lindex $argv 1] 
set password [lindex $argv 2] 
set timeout 10 
spawn ssh $user@$ip 
 expect {   
    "yes/no" { send "yes\n";exp_continue }         
    "password" { send "$password\n" } 
  } 
 expect "]#" { send "useradd haha\n" }
 expect "]#" { send "echo aaa|passwd --stdin haha\n" }
 send "exit\n" expect eof 
 #./ssh4.exp 192.168.8.100 root aa

shell调用expect

 #!/bin/bash 
  ip=$1  
  user=$2 
 password=$3 
  expect <<EOF  
      set timeout 10 
      spawn ssh $user@$ip 
      expect { 
          "yes/no" { send "yes\n";exp_continue } 
         "password" { send "$password\n" }
     } 
     expect "]#" { send "useradd hehe\n" } 
     expect "]#" { send "echo rrr|passwd --stdin hehe\n" } 
     expect "]#" { send "exit\n" } expect eof 
  EOF  
  #./ssh5.sh 192.168.8.100 root aaa